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<h1>Propylene glycol, C<sub>3</sub>H<sub>8</sub>O<sub>2</sub></h1>

Propylene glycol (C<sub>3</sub>H<sub>8</sub>O<sub>2</sub>) is a synthetic organic compound that is a colorless, nearly odorless, clear, viscous liquid with a faintly sweet taste. Often regarded as a safer alternative to ethylene glycol, it is miscible with a broad range of solvents including water, acetone, and chloroform. In industrial settings, propylene glycol is used as a moisturizer in cosmetics, as a food additive, in the manufacture of hydraulic fluids and as a coolant in liquid cooling systems. Pharmacologically, it's employed to help retain the moisture content in medicines and as a solvent for oral, injectable, and topical drugs. In the realm of optics, its refractive properties can be significant, especially when used as a matching or immersion fluid.

<h2>Other names</h2>
<ul>
<li>Propane-1,2-diol</li>
<li>α-Propylene glycol</li>
<li>1,2-Propanediol</li>
<li>1,2-Dihydroxypropane</li>
<li>Methyl ethyl glycol (MEG)</li>
<li>Methylethylene glycol</li>
</ul>

<h2>External links</h2>
<ul>
<li><a href="https://en.wikipedia.org/wiki/Propylene_glycol">Propylene glycol - Wikipedia</a></li>
<li><a href="https://webbook.nist.gov/cgi/cbook.cgi?ID=C57556">Propylene glycol - NIST Chemistry WebBook</a></li>
</ul>
